RootCanal: Rectify the value of the direction field in PCAP records

The value was inverted, which resulted in the packets read in wireshark
to be reported as coming from the opposite direction on the link.
The impact on HCI commands and events is minimal which explains
why it was not found sooner.

Test: manual
Change-Id: I4667ab318df1ac8346fb5c3c76765451daf9bfa5